Production method of microlens array, liquid crystal display device and production method thereof, and projector

Abstract

A method of producing a microlens array includes a patterning step of forming a first optical resin layer having a first refractive index on a transparent substrate and forming a plurality of microlens planes arrayed in a two-dimensional pattern on the front surface of the first optical resin layer; a planarizing step of forming a planarized second optical resin layer; a joining step of providing a support layer on which a transparent protective film is previously formed; and a removing step of removing the support layer in such a manner that only the protective film remains on the second optical resin layer. The planarizing step is performed by filling irregularities of the microlens planes with a resin having a second refractive index and planarizing the front surface, opposed to the microlens planes, of the resin, to form the planarized second optical resin layer, and the joining step is performed by joining the support layer to the planarized second optical resin layer. With this method, a microlens array excellent in surface accuracy and flatness can be produced without the need of provision of a support layer made from glass.

1 . A liquid crystal display device having a panel structure comprising: 
 a drive substrate on which at least pixel electrodes and switching devices for driving said pixel electrodes are formed;    a counter substrate on which at least a counter electrode is formed; and    a liquid crystal layer interposed between said drive substrate and said counter substrate joined such that said pixel electrodes are opposed to said counter electrode with a specific gap kept therebetween; wherein a microlens array composed of microlens arrayed in a two-dimensional pattern corresponding to an array pattern of said pixel electrodes is assembled at least to said drive substrate; and    wherein said microlens array has a stacked structure of a first optical resin layer having a first refractive index and a second optical resin layer having a second refractive index;    said first optical resin layer has microlens planes arrayed in a two-dimensional pattern, and said second optical resin layer is formed to fill irregularities of the microlens planes and has a planarized front surface opposed to the microlens planes; and said microlens array is assembled to said drive substrate in such a manner that the planarized surface of said second optical resin layer of said microlens array is joined to the back surface of said drive substrate.    
   
   
       2 . A liquid crystal display device according to  claim 1 , wherein said microlens array is formed by joining said first optical resin layer to a support layer having a protective film previously formed thereon with a specific gap kept therebetween, filling the gap with a liquid resin and curing said liquid resin to form said second optical resin layer, and removing said support layer to expose said protective film, the exposed surface of said protective film being taken as the planarized surface of said second optical resin layer.  
   
   
       3 . A liquid crystal display device according to  claim 1 , wherein said microlens array is formed by filling the microlens planes of said first optical resin layer with a resin, and pressing the front surface, opposed to the microlens planes, of said resin with a stamper having a flat plane, to planarize the front surface of said second optical resin layer.  
   
   
       4 . A liquid crystal display device according to  claim 1 , further comprising: 
 a microlens array disposed on said counter substrate in such a manner as to be aligned to said microlens array disposed on said drive substrate;    wherein one of said microlens arrays functions as condenser lenses and the other functions as field lenses.    
   
   
       5 . A liquid crystal display device according to  claim 1 , wherein said drive substrate is thinned by polishing the back surface thereof, and the planarized surface of said second optical resin layer of said microlens array is joined to the polished back surface of said drive substrate.  
   
   
       6 . A projector comprising: 
 a light source for emitting light; a liquid crystal display device having a function of optically modulating incident light; and    a projection lens for projecting light modulated by said liquid crystal display device;    said liquid crystal display device having a panel structure comprising:    a drive substrate on which at least pixel electrodes and switching devices for driving said pixel electrodes are formed;    a counter substrate on which at least a counter electrode is formed; and    a liquid crystal layer interposed between said drive substrate and said counter substrate joined such that said pixel electrodes are opposed to said counter electrode with a specific gap kept therebetween;    wherein a microlens array composed of microlens arrayed in a two-dimensional pattern corresponding to an array pattern of said pixel electrodes is assembled at least to said drive substrate; and    wherein said microlens array has a stacked structure of a first optical resin layer having a first refractive index and a second optical resin layer having a second refractive index;    said first optical resin layer has microlens planes arrayed in a two-dimensional pattern, and said second optical resin layer is formed to fill irregularities of the microlens planes and has a planarized front surface opposed to the microlens planes; and    said microlens array is assembled to said drive substrate in such a manner that the planarized surface of said second optical resin layer of said microlens array is joined to the back surface of said drive substrate.